He was born in the Chinese Year of the Hare. Like fellow members Leeteuk and Heechul, he’s a Cancer. At a height of 175 cm or 5'9", he’s one of Super Junior’s shortest members, along with Sungmin. They’re 10 cm shorter than the tallest member, Siwon. Ryeowook, Kangin, Shindong, and Eunhyuk’s blood type is O.

Ryeowook majored in theater arts at Inha University, where Leeteuk, Shindong, and Siwon also studied. He speaks Japanese. All of the members can speak some Mandarin. He’s an only child.

He was recruited by SM Entertainment back in 2004 through the CMB Youth ChinChin Festival. He debuted in Super Junior after only two months as a trainee. He’s a member of the sub-units Super Junior-K.R.Y. and Super Junior-M. Along with Siwon, Donghae, and Kyuhyun, he’s one of the first four Korean musicians ever to appear on a Chinese postage stamp. In 2015, he starred in The Curious Incident of the Dog in the Night Time. He plays the piano and keyboard.

Ryeowook always worries when the other members are sick. He says that if he were a woman, he’d marry Donghae.

He can sleep up to 18 hours a day. He has a mole on his right cheek. He searches on-line for all different types of websites, including anti-fan sites. He bought his parents a house.

When he’s drunk, Ryeowook goes around saying, “I love you,” over and over. According to Donghae, Ryeowook will cry first, then keep talking, then apologize, then go from room to room saying, “I love you.”